Respirator casing and methods of producing the same



Se t. 30, 1958 J. H. EMERSON 2,353,993

RESPIRATOR CASING AND METHODS OF PRODUCING THE SAME Filed Feb. 28, 19552 Sheets-Sheet 1 I i/ %//m///////////////A?//M% //////l 3- In van tor,

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P 1958 J. H. EMERSON 2,853,998

BESPIRATOR CASING AND METHODS OF PRODUCING THE SAME Filed Feb. 28, 1955'2 Sheets-Sheet 2 PLAIN EXP/(N050 (0.4750 OUTER COATING METAL WITHWEBB/N6 ADDED United States Patent RESPIRATOR CASING AND METHODS OFPRODUCING THE SAME John H. Emerson, Arlington, Mass. ApplicationFebruary 28, 1955, Serial No.'491,124

17 Claims. (Cl. 128-30) The present invention relates to respiratorcasings for inducing artificial respiration in a patient and to methodsof producing such casings.

The present application is a continuation in part of application SerialNo. 398,975 filed December 18, 1953. In that application there isdescribed a portable respirator casing made up of substantially twoparts: (1) a light troughlike cage adapted to be positioned over thepatients trunk with its edges resting against a support and (2) a sheetof flexible air-impervious material for placing over the cage with theforward and rear sides resting against the patients body and the othertucked between the patient and the support. Ordinarily the applicationto, and removal from, the patient of this type of respirator requires anattendant.

One object of the present invention is to provide a simple, portable,low cost, rugged, tough, tear and scrape resistant, air imperviousrespirator casing which comprises a single integral unit which is soeasily applied to and removed from the patient that the patient himselfcan apply and remove the same, which does not require any rigid orsemi-rigid back support along the patients back for supporting the same,the edges of which are adapted to be supported by the contours of thepatients body and form a substantially airtight seal therewith toprovide a substantially airtight chamber, the boundaries of which aredefined by the respirator casing and a minimum portion of the patientsanatomy, which does not necessarily form by itself or with a backsupport a chamber completely enclosing a portion of the patients trunk,as in known chest respirators, and which consequently is smaller, lessbulky, lighter and affords the patient greater convenience, comfort andfreedom of movement than any chest respirator known heretofore.

A still further object is to provide such a single integral unitrespirator which is so flexible thatthe edges can be easily shaped byhand to fit snugly enough against the contours of the bodies of patientshaving a variety of shapes thereof to form the above-mentionedsubstantially airtight contact therewith and hence the above-mentionedsubstantially airtight chamber but yet which is rigid enough to hold anyshape into which it is formed.

Other and further objects and advantages of the present invention willbe apparent from the following description and by reference to theaccompanying drawings, wherein:

Fig. 1 is a perspective view of a chest respirator embodying the presentinvention;

Fig. 2 is a longitudinal section taken on the line 22 of the respiratorof Fig. 1 with the respirator applied to a patients chest;

Fig. 3 is a section taken along the line 3-3 of Fig. 2;

Fig. 4 is a portion of an enlarged section taken along the line 4-4 ofFig. 1;

Fig. 5 is a plan View of a segment of the Web covered inner latticeframe of the respirator of Figs. 1 to 4 showing only a part of the webcovering, one side of such 2,853,998 Patented Sept. so, 1958 segment andonly a part of the web covering the other side thereof; and

Fig. 6 is a diagrammatic view of a segment of the respirator of Figs. 1to 4 during the stages of manufacture thereof, showing the same beforeit was covered with a layer of webbing (left), after both sides thereofwere covered with a layer of webbing (center) and the finishedrespirator after the web covered lattice frame was embedded in an airimpervious layer of tough, flexible, air impervious material.

Referring to Figs. 1 to 5, the chest respirator casing 1 of the presentinvention comprises a trough-shaped frame 2 which has a greater lengththan width and which is comprised of a relatively thin, expanded metalwhich is flexible enough to be easily formed by hand into any desiredshape but which is rigid enough to hold any shape into which it isformed. The top portion of frame 2 has an upward frusto-conicalextension 3, the top 4 of which is horizontal (see Figs. 2 and 4). Anaperture 5 extends vertically through horizontal portion 4. Welded tothe top of horizontal portion 4 is a metal plate 6 having an aperture 7(see Fig. 4) aligned with aper: ture 5.

. End portions 8 (see Figs. 3 and 4) of two flat, metal ears 9 arewelded to the sides of frame 2 as shown. Each end portion 8 of each ear9 extends at an angle into portion 10 (see Fig. 4) which has two slots11 passing therethrough.

Frame 2 has an outwardly flared portion 12 (see Figs. 2 and 4) along thebottom thereof, the lower edge of which turns inwardly at 12a andupwardly at 13 to form a reinforced edge. The entire frame has a layerof cheese cloth 14 (Fig. 5) or any other kind of flexible, light, porousweb or mesh of a thread-like flexible fiber or filament covering bothsides thereof. The cheese cloth 14 extends over and between the spacesformed by the strips of expanded metal of frame 2 (see Fig. 5), but doesnot extend over and between the apertures 5 and 7 of frame 2 and plate 6respectively.

The cheese cloth covered frame 2, the ears 9 and the plate 6 areembedded in an air impervious layer 15 of a tough, flexible, airimpervious, rubber-like material such as a plasticized vinyl chloridepolymer or copolymer or a natural or artificial rubber. In the figures,such layer 15 is comprised of a high molecular weight plasticized vinylchloride polymer. Although the layer 15 extends across and fills in thespaces between the metal strips of the expanded metal frame 2, it doesnot extend across the apertures 5 and 7, but merely covers the edgesthereof to form an aperture 16 (see Fig. 4), the edges of which arereceived in a circumferential groove 17 of a rubber grommet 13 having apassage 19 which is adapted to receive the narrow portion 20 (Fig. 2) ofa tube connector 21 to which is attached tube 22 leading to analternating source of negative and atmospheric pressure, positive andatmospheric pressure, or negative and atmospheric pressure. However, thesource of pressure, as well as the tubing 22, forms no part ofapplicants present invention which is drawn to the respirator casingitself.

For the purpose of simplification, in the drawings the same numeralsthat are used to indicate particular portions of frame 2 and ears 9 areused to indicate such portions covered by the gauze 14 and/or embeddedin layer 15.

of frame 2' isembedded while the lower'po'rtion thereof extends beyondthe lower edge of embedded frame 2 as shown. Pad 23 is further securedto embedded frame 2 by means of a strip of tape 24 taped to the outersurface of the lower portion of pad 23 and to the outer surface of thelayer 15 in which portion 12 of frame 2 is embedded. Removably attachedto portion of cars 9 (Figs. 2 and 3) by means of slots 11 is a strap 26for strapping the respirator casing 1 to the patients chest, as shown inFigs. 2 and 3.

Since the frame 2 is sufficiently flexible to be formed by hand into anyshape desired and since the layer of material 15 in which it is embeddedis flexible, the respirator 1 can be easily formed by hand into theshape shown in Figs. 2 and 3 so that the flat inner surface 23a ofcushioning and sealing pad 23 will fit substantially along its entirewidth and length snugly and in a substantially airtight manner againstthe contours of the pa- 7 tients body, as shown, when the casing is heldfirmly against such contours by strap 26 passing through slots 11 andaround the patients back as shown, whereby a substantially airtightchamber 30 is formed by the walls of the respirator casing 1 and portion31 of the patients :body. Since frame 2 is sufficiently rigid to retainany shape into which it is formed, once respirator casing 1 has beenformed by hand into the shape shown so that the above mentioned snug fitis obtained between the edges thereof and the contours of the patientsbody, the respirator will retain such shape until it is deliberatelytwisted out of such shape by hand or by an instrument. Frame 2 lendssufficient rigidity to the casing to prevent it from being forcedsubstantially out of shape either by the handling to which therespirator is ordinarily subjected while it is operably attached to thepatient or by the changes of pressure which occur within chamber 30during artificial respiration.

Cushioning and sealing pad 23 assures a snug, substantially airtight fitbetween the patients body and the respirator and prevents the edges ofthe respirator casing from biting into the patients body during the usethereof. Portion 12 of frame 2 is outwardly flared in order to permit amaximum amount of the broad surface 23a of cushioning and sealing pad 23to fit as flush as possible against the patients body so as to assure asubstantially airtight as well as a comfortable fit between the edges ofthe respirator casing and the patients body. The flare thereof may beadjusted by hand to assure in each instance that surface 23a will fit asflush possible. The cushioning and sealing pad 23 is made from a veryresilient and flexible vinyl plastic or rubber gasketing material sothat it will easily take on the contour of the patients body and fitsnugly thereagainst in an airtight manner when the respirator is heldfirmly against the patients body by means of strap 26 or by hand.

Although the frame 2 of the drawings is made of expanded metal, it canbe made of any similar material or design so long as it is flexibleenough to be formed easily by hand into any shape desired and at thesame time is rigid enough to retain any shape into which it is formed.Chicken wire or any other similar wire mesh having these properties issuitable. A lattice shape is preferred because it makes possible alighter respirator and permits the use of materials which in the form ofa solid sheet would not be sufliciently flexible.

In manufacturing the respirator shown in the drawings, the expandedmetal frame was formed in a known manner with an aperture 5 in themiddle thereof and shaped by hand or otherwise into the desired shape. Asmall section of such expanded metal at this stage is showndiagrammatically on the left of Fig. 6. Plate 6 and ears 9 were thenwelded or attached in any other manner to the frame as shown. Thelattice frame was then covered on both sides with a layer of lightweight, porous cheese cloth so that the layers of cheese cloth extendedover the spaces of the lattice frame but not over apertures 5 and 7. Thetwo layers of cheese cloth were tacked together at a number of pointstherealong. The small section of the frame referred to above is showndiagrammatically at this stage in the middle of Fig. 6. The cheese clothcovered frame was then immersed in a bath of cream Chem-o-sol R3506[trademark for a vinylchloride polymer plastisol (liquid dispersion of ahigh molecular weight vinyl chloride polymer resin in a liquidplasticizer) sold by Chemical Products Corporation] for a period of fromfour to ten minutes, it was then suspended over the tank and allowed todrain for from four to six hours, and it was then placed in a closedoven at 350 F. for a period of from ten to twenty minutes after which itwas removed and cooled to room temperature. The liquid Chem-osol, whichadheres to the cheese cloth covered frame from the immersion or dippingstep, formed, during the heating and cooling steps a tough, flexiblelayer of plasticized vinyl chloride polymer in which the cheese clothcovered frame, plate 6 and ears 9 were embedded as' shown. The segmentreferred to above at this stage is shown diagrammatically at the rightof Fig. 6.

The layer of resin 15 adheres strongly to the frame 2 and fills up thespaces between the strips of metal thereof. It can be removed therefromonly with great difliculty.

The cheese cloth 14 is used to bridge the gaps between the strips ofexpanded metal so as to form a base therebetween to which the liquidplastisol can adhere. Consequently, a continuous air impervious layer 15of plasticized vinyl chloride resin is formed which extends across andfills in such gaps so that the entire frame is embedded in such layer.If the cheese cloth is omitted, the liquid dispersion adheres only tothe surfaces of the metal strips and when it is cured by heating eachindividual strip has a coating of resin therearound with gaps or spacestherebetween. Instead of cheese cloth, any light weight, porous web ormesh of fine fibers or threadlike filaments may be used so long as itbridges the gaps and consequently forms a base therebetween to which thedispersion can adhere and so long :as it can be flexed freely. In fact,rubber can be sprayed over both sides of the frame in the form ofthread-like filaments and in a known manner to form rubber cobwebs whichadhere to the metal strips and extend over the gaps therebetween. Theweb should be porous and light weight so that the dispersion can passtherethrough and contact the metal strips during the dipping. It shouldbe flexible so that it will not interfere with the flexibility of thecas- Any flexible, tough, rubber-like resin, rubber or artificial rubbercan be used instead of vinyl chloride polymers to form the outer layerof flexible material so long as it is flexible enough so that the finalrespirator casing can be formed easily by hand as set forth above and solong as it is gas impervious, tough and tear resistant. Resins formedfrom polymerizable, unsaturated compounds, and having such properties,such as vinyl resins and natural or artificial rubber are preferred, themost suitable being high molecular weight vinyl chloride polymers andcopolymers.

The layer of flexible material may be applied in any liquid form, forexample, as a solution of resin or rubber in an organic solvent, as adispersion or emulsion in water or other liquids (latex) or as adispersion in a liquid plasticizer for the resin (plastisol) as setforth above. When a thermoplastic resin or rubber solution or latex isused which has a solvent or carrier which must be driven off before theresin is cured, the adhered coating of liquid should be dried and thenheated to cure the resin particles and cause them to fuse together intoa continuous layer. Sheets of thermoplastic resinous material may belaid on either side of the frame 2 and then heated and pressed so as tofuse together and form a continuous layer in which the frame isembedded.

Any type of cushioning or sealing pad can be used so long as it isflexible enough and of a design to afford a comfortable snug andairtight seal between the respirator casing and the contours of thepatients body. For example, an air filled, flexible, rubber tube of thetype ordinarily used in oxygen masks is suitable. The particular flareof portion 12 of frame 2 depends on the type and shape of pad used andmay be omitted entirely if the pad is designed and shaped to produce acomfortable airtight fit without it.

When the chest respirator casing of Figs. 1 to 5 is applied to thepatients chest, as shown, chamber 30 is sufficiently airtight to permita negative pressure to be built up therein during operation of therespirator. As the negative pressure is built up in chamber 30 the edgesof the respirator are sucked more tightly against the patients body andconsequently the seal between ring 23 and the patients body becomes moreairtight.

The respirator casing, when used as a chest respirator as in Figs. 1 to5, is preferably of a size so that the edge toward the patients headrests along the vicinity of the patients collar bone, the edge towardthe patients feet rests on the lower part of his abdomen adjacent to hispubic bone and the side edges rest on the side of the patients bodyunder his arms.

Although in the drawings of Figs. 1 to 5 all the edges of the respiratorlie against the patients body so that no back support for the patient isneeded to support the edges of the respirator as in prior art devices,it is apparent that the respirator of the present invention can be usedwith a back support, the extreme flexibility of such respirator beingtaken advantage of to obtain a snug, close fit between the patients bodyand the respirator and the support and the respirator.

It is understood that any satisfactory means can be used to hold therespirator against the body besides the ears and strap as shown. In factit can be held against the patients body by the patient himself.

The particular manner in which the aperture in the top of the casing isformed may be varied in any manner desired.

The edges of the chest respirator coming in contact with the patientsbody and the portions of the respirator adjacent thereto may beconstructed in any manner desired so long as such edges are adapted tofit snugly against the patients body without undue discomfort to thepatient.

The terms chest respirator and chest respirator casing as used hereinincludes any respirator and respirator casing which enclose a sufficientportion of the trunk of a patient to induce artificial respiration inthe patient.

Although the respirator casing of the present invention is most usefulas a chest respirator, it can also be used as a resuscitator or facemask type respirator, it being understood that when it is so used thesize and shape thereof should be such that it is adapted to fit over themouth and nose or the mouth, noseand eyes of the patient. The termsrespirator and respirator casing, as used herein, include chestrespirators and respirator casings and resuscitator or face mask typerespirators and respirator casings.

Although the embedded lattice structure of the present invention hasbeen described and shown in a respirator casing construction, it isapparent that it can be used for other purposes. When such a structureis used in a respirator casing of the type described and shown above,the frame 2 should be flexible enough to be readily formed by hand intoany desired shape. However, other uses thereof might require latticeframe 2 to be much stiffer. l

The respirator of the present invention comprises a single unit,extremely light respirator, which is so easy to apply to and remove fromthe patient that he can do it himself, which can be fitted to patientshaving a variety of chest and face sizes, which does not require a backsupport and which covers a minimum of body area, thereby permitting itto be less bulky and lighter than known chest respirators to aiford thepatient a maximumof convenience, comfort and freedom of movement.

While I have shown and described one embodiment of my invention, it isto be understood that this disclosure is for the purpose of illustrationonly and various changes and substitutions of equivalent elements may bemade without departing from the spirit of the invention as set forth inthe appended claims.

I claim:

1. A respirator casing comprising a concave shaped, air impervious cagewhich is sufliciently flexible to be formed by hand into any desiredshape but which is sufficiently rigid to hold any shape into which it isformed, the edges of said cage being adapted to be formed by hand to fitsnugly against selected contours of a patients body in a substantiallyairtight manner to form a chamber around a portion of said body, saidchamber being substantially airtight when said edges are held firmlyagainst said contours, said cage having a passage extending therethroughadapted to provide communication between the interior and exterior ofsaid chamber and comprising a light base shell which is sufficientlyflexible to be formed by hand into a desired shape but which is n'gidenough to hold any shape into which it is formed and which is latticeshaped, said shell being embedded in a gas impervious layer of a tough,flexible elastic, thermoplastic resin, said layer of resin extendingacross and filling the gaps of said lattice to form a continuous layerin which said lattice shaped shell is embedded.

2. A respirator casing comprising a concave shaped, airimpervious cagewhich is sufliciently flexible to be formed by hand into any desiredshape but which is sufficiently rigid to hold any shape into which it isformed, the edges of said cage being adapted to be formed by hand to fitsnugly against selected contours of a patients body in a substantiallyairtight manner to form a chamber around a portion of said body, saidchamber being substantially airtight when said edges are held firmlyagainst said contours, said cage having a passage extending therethroughadapted to provide communication between the interior and exterior ofsaid chamber and comprising a light base shell which is sufficientlyflexible to be formed by hand into a desired shape but which is rigidenough to hold any shape into which it is formed and which islattice-shaped, said shell being embedded in a gas impervious layer of atough, flexible material, said layer of flexible material extendingacross and filling the gaps of said lattice to form a continuous layerin which said lattice-shaped shell is embedded, said latticeshaped shellbeing covered by a light, porous web of flexible, thread-like filamentswhich extends across the gaps thereof, said web covered lattice-shapedshell being embedded in said continuous layer of gas impervious, tough,flexible material which extends across and fills the gaps of saidlattice-shaped shell.

3. A chest respirator casing comprising a trough-like, air imperviouscage which is sufficiently flexible to be formed by hand into anydesired shape but which is sufficiently rigid to hold any shape intowhich it is formed, the edges of said cage being adapted to be formed byhand to fit snugly against selected contours of a patients trunk to forma chamber along at least a sufficient portion of said trunk to induceartificial respiration in the patient, said chamber being bounded bysaid cage and said portion and being substantially airtight against saidcontours, and said cage having a passage ex- .tending therethroughadapted to provide communication between the interior and the exteriorof said chamber and comprising a light base shell which is sufficientlyflexible to be formed by hand into any desired shape but which is rigidenough to hold any shape into which it is formed, said shell beingembedded in a gas impervious layer of a tough, flexible elasticthermoplastic resin.

4. The respirator of claim 1 having a resilient, flexible cushioning andsealing means located along the edges thereof for contacting saidcontours in a comfortable and airtight manner.

5. The respirator of claim 1 wherein said shell is lattice-shaped andsaid layer of flexible resin extends across and fills the gaps of saidlattice-shaped shell to form a continuous layer in which saidlattice-shaped shell is embedded.

6. A chest respirator casing comprising a trough-like, air imperviouscage which is sufficiently flexible to be formed by hand into anydesired shape but which is sufficiently rigid to hold any shape intowhich it is formed, the edges of said cage being adapted to be formed byhand to fit snugly against selected contours of a patients trunk to forma chamber around at least a. suificient portion of said trunk to induceartificial respiration in the patient, said chamber being bounded bysaid cage and said portion and being substantially airtight against saidcontours,

. and said cage having a passage extending therethrough adapted toprovide communication between the interior and the exterior of saidchamber and comprising a light base shell which is sufficiently flexibleto be formed by hand into any desired shape but which is rigid enough tohold. any shape into which it is formed, said shell being embedded in agas impervious layer of a tough, flexible material, said lattice-shapedshell is covered by a lightweight, porous, fiexible web of materialwhich extends across the gap-s thereof, said web covered lattice-shapedshell being embedded in said continuous gas impervious layer of tough,l'lexible material, which extends across and fills the gaps of saidlattice-shaped shell.

7. The respirator of claim 6 wherein said base shell is made fromexpanded metal and said web comprises a web of fine, flexible,thread-like filaments which extend over and between the gaps of theexpanded metal.

8. The respirator of claim 7 wherein said lattice-shaped shell is foldedover at its edges and said cage has a rim of resilient cushioning andsealing material along the edges thereof.

9. The respirator of claim 8 wherein said web comprises a thin gauze andsaid resilient material comprises a vinyl chloride resin.

10. A process for producing a respirator casing comprising forming atrough-shaped lattice which is suificiently flexible to be formed byhand to any desired shape but which is rigid enough to hold any shapeinto which it is formed, said lattice having an enlarged aperturetherethrough, applying over said lattice but not over said aperture athin web of flexible thread-like filaments which extends across andbetween the gaps thereof and applying to and around said web coveredlattice a continuous, gas impervious layer of a tough, flexible materialin which said web covered lattice is embedded and which extends acrossand fills in the gaps of said lattice.

11. The process of claim 10 wherein said layer of flexible material isapplied to and around said web covered lattice by dipping the same intosaid flexible material while it is in the form of a liquid andsubsequently solidifying the coating of material which adheres to saidweb covered lattice.

12. A gas and liquid imprevious structure comprising a lattice-shapedframe, a light, porous web of thread-like filaments covering saidlattice frame and extending across the gaps thereof, said web coveredlattice frame being embedded in a continuous, gas and liquid imperviouslayer of a tough flexible material which extends across and fills thegaps of said lattice frame.

13. A method for producing a gas and liquid impermeable structurecomprising covering a lattice or frame with a light, porous web ofthread-like filaments and embedding said web covered lattice frame in agas and liquid impervious layer of a tough, flexible material, whichextends across and fills in the gaps of said frame.

14. The respirator of claim 1 wherein said resin comprises a vinylresin.

15. The respirator of claim 14 wherein said resin comprises a solidifiedplastisol of a vinyl chloride polymer.

16. The respirator of claim 3 wherein said resin comprises a vinylresin.

17 The respirator of claim 16 wherein said resin comprises a solidifiedplastisol of a vinyl chloride polymer.

References Cited in the file of this patent UNITED STATES PATENTS1,359,073 King Nov. 16, 1920 1,632,449 McKesson June 14, 1927 2,360,476Church Oct. 17, 1944 2,707,948 Emerson May 10, 1955

